A Phase II, Open-Label, Randomized Study to Assess the Efficacy and Safety of AZD6244 (ARRY-142886) Versus Pemetrexed in Patients with Non-small Cell Lung Cancer Who Have Failed One or Two Prior Chemotherapeutic Regimens

Introduction: AZD6244 (ARRY-142886) is a potent, selective MEK inhibitor. This study aimed to evaluate the efficacy and safety of AZD6244 versus pemetrexed as second- or third-line treatment in patients with advanced non-small cell lung cancer (NSCLC). Methods: In this randomized phase II study, patients received either 100 mg oral AZD6244 free-base suspension twice daily or 500 mg/m 2 intravenous pemetrexed once every 3 weeks after pretreatment with a corticosteroid, folic acid, and vitamin B12. The primary end point of the study was the disease progression event count. Results: Eighty-four patients were randomized. Disease progression events were experienced by 28 (70%) and 26 (59%) patients in the AZD6244 and pemetrexed groups, respectively. Median progression-free survival was not statistically significantly different between the AZD6244 and pemetrexed groups (67 versus 90 days, respectively; hazard ratio 1.08, two-sided 80% confidence interval=0.75–1.54; p = 0.79). Two patients in the AZD6244 group had a best response to treatment of partial response. In the pemetrexed group, one patient achieved a complete response and one patient a partial response. Dermatitis acneiform, diarrhea, nausea, and vomiting were the most frequently reported adverse events with AZD6244, compared with fatigue, anemia, nausea, anorexia, and dermatitis acneiform with pemetrexed. Conclusions: Oral AZD6244 showed clinical activity as second- or third-line therapy for patients with advanced NSCLC. In an unselected NSCLC population, there is no suggestion that AZD6244 monotherapy offers any advantage over standard treatment with pemetrexed. Based on preclinical data and recent clinical observations, further development of AZD6244 in NSCLC should focus on BRAF or RAS mutation-positive patients and/or AZD6244-based combination regimens.